<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .dbsjx{
            width: 0px;
            border-style:  solid;
            border-top-width: 220px;
            border-right-width:450px;
            border-color: red transparent transparent  transparent;
            
        }

        .box{
            border-radius: 100px;
            width: 500px;
            height:200px;
            background-color: yellowgreen;
        }

        .zj{
            width: 0px;
            border-style:  solid;
            border-top-width: 500px;
            border-left-width: 200px;
            border-color: red transparent transparent;
        }

        .d{
            width: 0px;
            border-style: solid;
            border-width: 100px 100px 100px 100px;
            border-color: transparent transparent red transparent;
            
        }

    </style>
</head>
<body>
    <div class="dbsjx"></div>
    <div class="box"></div>
    <div class="zj"></div>
    <div class="d"></div>
</body>
</html>